92 s10 blazer:glowing exhaust manifolds

[ex-tex]

Ok guys my 92 had (before motor rebuild) and still has the same power lose as member Drive24's did even after a fresh rebuild, now I can't get the timing to stay in one spot and I noticed this morning that while trying to set the timing the exhaust manifolds were turning fire red. When I first turned it over without the exhaust pipes on, I noticed fire shuting out of the exhaust manifolds, I thought it was from no back pressure, but now I dont know. still dont have power going up hills. any thoughts???? Thanks

[Rick Norwood]

Originally Posted by ex-tex

Ok guys my 92 had (before motor rebuild) and still has the same power lose as member Drive24's did even after a fresh rebuild, now I can't get the timing to stay in one spot and I noticed this morning that while trying to set the timing the exhaust manifolds were turning fire red. When I first turned it over without the exhaust pipes on, I noticed fire shuting out of the exhaust manifolds, I thought it was from no back pressure, but now I dont know. still dont have power going up hills. any thoughts???? Thanks

This happened to my 2001 only the exhaust pipes were red but I didn't check the manifolds.

What is happening is unburned fuel is being blown into the exhaust system and igniting when it hits the hot metal. MY PROBLEM was the distributor itself. The distributor shaft bearing/bushing was worn so bad that you could wiggle the shaft from side to side over a half inch. The Rotor inside the distributor finally broke off inside of the distributor and the engine quit all together.

$1600, two catalitic converters, a new distributor, O2 sensors, and few other parts later, we're good.

DO NOT DRIVE OR START THE VEHICLE UNTIL YOU FIGURE THIS OUT OR YOU WILL IN ALL LIKELIHOOD DO MORE DAMAGE.

The spark should be controlled by the ECM, and should not be jumping around. Remove your distributor cap and try to wiggle the shaft from side to side, it should not move more that a few thousandths of an inch. If you can wiggle it by hand, you will need to rebuild or replace your distributor.

Good Luck

[ex-tex]

would that also make it sound like it has a slight exhaust leak?

[Airjer_]

plugged cats could cause that!

[Rick Norwood]

Originally Posted by ex-tex

would that also make it sound like it has a slight exhaust leak?

I am sure it probably would. With the exhaust system taking on all of the added temperature and pressure that it isn't design to take not to mention the metal expansion due to the high heat, I would be surprised if it didn't leak. Mine melted the Cats and the O2 sensors.

I would take this one step at a time. Find the timing issue first then see about any possible leak.

[Rick Norwood]

Originally Posted by Airjer_

plugged cats could cause that!

He said it was happening even without the manifolds on. This is unburned fuel blowing out of the combustion chamber. But you will Melt, plug, and destroy the cats if you keep running the engine like this.

[ex-tex]

ok checked distributor, cant move by hand. when moving the timing i notice when i get to 0 degrees it jumps up to about 4, when it get it back to 0 from there it drops to about -6. I have not changed the EGR valve out just cleaned, new o2 senser. the fire red on the manifolds where on the #3,5, and 6 cylinders after driveing 15 miles( if that makes sense) . Do I need to change out the EGR valve or would another senser make this happen??

[ex-tex]

also I was told by a mechanic (when I had it inspected) that the high idle was from running lean, and I needed to change the EGR valve. But all I did was clean the sticking plunger????

[Rick Norwood]

Are you getting any SES lights or Check engine lights or codes? According to the mechanics that fixed mine, the ORIGINAL problem was a bad MAF sensor. I am not 100% convinced of this, but they claim that is what started the problem. It was throwing codes, but I think most of my problem was the distributor. In any event, they zonked me for $300 for a new MAF sensor claiming I would repeat the entire episode if I left the old one in there. Whadda going to do?

[ex-tex]

havent checked codes, but the only time i get the check engine light is when im checking timing.

[ex-tex]

I dont have a reader for this blazer. only thing i know to do is jump out the 2 terminals and count the flashes.

[Rick Norwood]

Originally Posted by ex-tex

I dont have a reader for this blazer. only thing i know to do is jump out the 2 terminals and count the flashes.

What are the codes?

[Airjer_]

Originally Posted by ex-tex

would that also make it sound like it has a slight exhaust leak?

Originally Posted by airjer_

plugged cats could cause that!

That should make it a little clearer on what I was replying to.

[ex-tex]

only getting 3 codes, 22, 23, and 42

[Rick Norwood]

Originally Posted by ex-tex

only getting 3 codes, 22, 23, and 42

See this thread in the How-To section. Thanks Blazee:

http://www.automotiveforums.com/vbul...d.php?t=553044